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TypeError: Cannot assign to read only property 'callback' of decr

See original GitHub issue

Version: node redis 2.6.2
Platform: Node 4.4.5 on Ubuntu 14.04
Description: I keep getting this error while trying to decrement a simple online counter in redis:

    TypeError: Cannot assign to read only property 'callback' of decr
    at RedisClient.internalSendCommandWrapper (/home/alex/node_modules/newrelic/lib/instrumentation/redis.js:76:22)
    at RedisClient.wrappedFunction [as internal_send_command] (/home/alex/node_modules/newrelic/lib/transaction/tracer/index.js:354:24)
    at RedisClient.(anonymous function).RedisClient.(anonymous function) (/home/alex/node_modules/redis/lib/commands.js:45:25)
    at Socket.eval (eval at <anonymous> (/home/alex/server2.js:2:52), <anonymous>:2456:12)
    at emitOne (events.js:77:13)
    at Socket.emit (events.js:169:7)
    at Socket.emit (/home/alex/node_modules/socket.io/lib/socket.js:128:10)
    at Socket.onclose (/home/alex/node_modules/socket.io/lib/socket.js:425:8)
    at Client.onclose (/home/alex/node_modules/socket.io/lib/client.js:232:24)
    at Client.onerror (/home/alex/node_modules/socket.io/lib/client.js:213:8)

The code is:

    db.decr('online',function(err){
        if(err){
            console.log('DECREMENTING ONLINE NUMBER FAILED:');
            console.log(err);
        }
        console.log('DECREMENTING ONLINE NUMBER WAS SUCCESSFUL!');
    });

I can’t seem to replicate it, but it only happens when lots of people are on the site. When it’s only me and a couple of friends testing it it seems to do the job just fine incrementing and decrementing the value.

By the way it happens even without the callback function (just db.decr(‘online’)), I only added the callback to see if it would throw any errors.

I repeat, the code works fine until more people start using it. Maybe it’s trying to do .decr at the same time and it can’t handle that or?

Issue Analytics

State:
Created 7 years ago
Comments:6 (1 by maintainers)

Top GitHub Comments

3reactions

landaucommented, Jul 21, 2016

I just hit this problem with redis@2.6.0-2 and newrelic@1.28.3. Setting newrelic back to 1.28.0 removed the issue.

However, using redis 2.6.2 and newrelic 1.28.3 works fine.

1reaction

BridgeARcommented, Jun 23, 2016

This seems to be a issue with newrelic, so I recommend to contact them about this. I’m sorry that I can’t help you any more, as I do not use newrelic on my own.

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